Centos5 error

Whenever I install Centos5, I always forget to do two things:
1. edit /etc/yum.conf and include
proxy=http://{ip address of proxy}:{port number}

2. import gpg key
cd /etc/pki/rpm-gpg
rpm --import RPM-GPG-KEY-CentOS-5

This will allow me to run:
yum -y update

without "GPG key retrieval failedL [Errno 4] IOError:

This is a lot easier than added http_proxy to your .bashrc file and exporting, and all the other solutions others guess at on internet forums.